OSMIA AND ITS HABITS 57 



which had been left in a garden- arbour. The 

 bee constructed fourteen cells in the tube of the 

 instrument, commencing its first cell a quarter 

 of an inch below the mouthhole. The flute is pre- 

 served in the Natural History Museum at South 

 Kensington. At other times this species burrows 

 in the ground, at others it makes its cells in 

 crevices of old walls ; it has been known to build 

 in a lock, and is said sometimes to inhabit snail 

 shells. Other species of Osmia almost always 

 burrow in banks, but in no case does a habit 

 seem to be uniformly adopted by a species. 

 One well known and rare species, Osmia leucome- 

 lana, is a regular bramble-stick species, tunnelling 

 down the pith in the centre of the stalks, but I 

 once found it to my surprise in fair numbers 

 nesting in a sandy bank. Other species again, as 

 a rule, select snail shells to build in ; they find 

 an old disused shell lying about in some sheltered 

 place and adapt it to their purposes, commencing 

 their cells singly in the narrow whorls of the 

 shell and side by side as they approach its mouth, 

 i.e. if the shell be a wide-mouthed one like the 

 common garden snail (Hdix aspersa). F. Smith, 

 who gives a very interesting account of these 



